Batch-Type Remote Plasma Processing Apparatus

ABSTRACT

A plasma processing apparatus comprises a processing chamber in which a plurality of substrates are stacked and accommodated; a pair of electrodes extending in the stacking direction of the plurality of substrates, which are disposed at one side of the plurality of substrates in said processing chamber, and to which high frequency electricity is applied; and a gas supply member which supplies processing gas into a space between the pair of electrodes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a plasma processing apparatus, and moreparticularly, to a batch-type remote plasma processing apparatus, e.g.,to an apparatus which is effectively utilized for depositing aninsulative film or a metal film on a semiconductor wafer (wafer,hereinafter) on which a semiconductor integrated circuit includingsemiconductor elements is formed in producing a semiconductor device.

2. Description of the Related Art

As a conventional batch-type remote plasma processing apparatus, asingle wafer-feeding type remote plasma CVD apparatus has been used.However, in the single wafer-feeding type remote plasma CVD apparatus,since wafers are processed one by one, there has been a problem thatthroughput is small.

SUMMARY OF THE INVENTION

Therefore, it is a main object of the present invention to provide aplasma processing apparatus capable of obtaining great throughput.

According to a first aspect of the present invention, there is provideda plasma processing apparatus, comprising:

a processing chamber in which a plurality of substrates are stacked andaccommodated,

a pair of electrodes extending in the stacking direction of theplurality of substrates, the electrodes being disposed at one side ofthe plurality of substrates in the processing chamber, and highfrequency electricity being applied to the electrodes, and

a gas supply member which supplies processing gas into a space betweenthe pair of electrodes.

According to a second aspect of the present invention, there is provideda plasma processing apparatus, comprising:

a processing chamber in which a plurality of substrates are stacked andaccommodated,

a pair of electrodes which is disposed inside and outside of theprocessing chamber such as to be opposed to each other at one side ofthe plurality of substrates, and to which high frequency electricity isapplied, and

a gas supplying pipe which supplies processing gas into the processingchamber to a place which is away from the space between the pair ofelectrodes.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and further objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription taken in conjunction with the accompanying drawings,wherein:

FIG. 1 is a transversal sectional view of a CVD apparatus according to afirst embodiment of the present invention;

FIG. 2 is a longitudinal sectional view taken along a line II-II of FIG.1;

FIG. 3 is a longitudinal sectional view taken along a line III-III ofFIG. 1;

FIG. 4 is a transversal sectional view of a CVD apparatus according to asecond embodiment of the present invention;

FIG. 5 is a longitudinal sectional view taken along a line V-V of FIG.4;

FIG. 6 is a transversal sectional view of a CVD apparatus according to athird embodiment of the present invention;

FIG. 7 is a longitudinal sectional view taken along a line VII-VII ofFIG. 6;

FIG. 8 is a longitudinal sectional view taken along a line VIII-VIII ofFIG. 6;

FIG. 9 is a transversal sectional view of a CVD apparatus according to afourth embodiment of the present invention;

FIG. 10 is a transversal sectional view of a CVD apparatus according tothe fourth embodiment of the present invention;

FIG. 11 is a longitudinal sectional view taken along a line X-X of FIG.9;

FIG. 12 is a longitudinal sectional view taken along a line XI-XI ofFIG. 9;

FIG. 13 is a transversal sectional view of a CVD apparatus according toa fifth embodiment of the present invention;

FIG. 14 is a longitudinal sectional view taken along a line XIII-XIII ofFIG. 12; and

FIG. 15 is a longitudinal sectional view taken along a line XIV-XIV ofFIG. 12.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In order to form a capacitance portion (insulative film) of a capacitorof a DRAM (Dynamic Random Access Memory) which is one example of asemiconductor integrated circuit apparatus, studies are carried out forusing a tantalum pentoxide (Ta₂O₅). Since Ta₂O₅ has high dielectricconstant, it is suitable for obtaining great capacitance with a finearea. In a producing method of the DRAM, it is desired to form a Ta₂O₅film by an MOCVC apparatus in view of productivity, quality of film andthe like.

It is know that if the Ta₂O₅ film is formed by the MOCVD apparatus,carbon (C) which may generate leak current adheres to a surface of theTa₂O₅ film or in the vicinity of the surface. Therefore, after the Ta₂O₅film is formed on a wafer, it is necessary to eliminate carbon existingin the vicinity of the surface of the Ta₂O₅ film. A single wafer-feedingtype remote plasma CVD apparatus can lower a heating temperature of awafer to 300 to 400° C. while preventing plasma damage of a wafer.Therefore, studies are carried out for eliminating the carbon on a Ta₂O₅film by the single wafer-feeding type remote plasma CVD apparatus.

In the single wafer-feeding type remote plasma CVD apparatus, however,since carbon of the Ta₂O₅ film is eliminated one by one, there is aproblem that throughput becomes small. For example, if net processingtime in a single wafer-feeding type remote plasma CVD apparatus is tenminutes and operation time of a transfer system is two minutes, theprocessing number of wafers per one hour is as small as five.

A general single wafer-feeding type remote plasma CVD apparatus is of acold wall type in which only a susceptor is heated to a processingtemperature. Therefore, in such a single wafer-feeding type remoteplasma CVD apparatus, there are problems that it is difficult touniformly heat the entire surface of a wafer, and it is difficult toheat the wafer to 400° C. or higher due to a problem of selection ofmaterial of a chamber. Further, when a heater is embedded into asusceptor and a wafer is heated, since heat is not uniformly transferredto the wafer due to warpage of the wafer or roughness of a surface ofthe wafer, it is difficult to heat the wafer to 500° C.±1%. Therefore,it is conceived to use a heater having an electrostatic fastener, butthe heater having an electrostatic fastener is extremely expensive, andthe reliability is low with respect to its price.

It is, therefore, a main object of preferred embodiment of the presentinvention to provide a plasma processing apparatus capable of obtaininggreat throughput, and capable of enhancing uniformity of a temperatureof a substrate to be processed.

A plasma processing apparatus according to one preferred aspect of thepresent invention, comprises:

a processing chamber in which a plurality of substrates are stacked andaccommodated, and

a pair of electrodes extending in the stacking direction of theplurality of substrates, the electrodes being disposed at one side ofsaid plurality of substrates in the processing chamber, and highfrequency electricity being applied to the electrodes, wherein

the processing apparatus is constituted such that processing gas issupplied into a space between the pair of electrodes.

A plasma processing apparatus according to another aspect of the presentinvention, comprises:

a processing chamber in which a plurality of substrates are stacked andaccommodated, and

a pair of electrodes extending in the stacking direction of theplurality of substrates the electrodes being disposed inside and outsideof the processing chamber and at one side of the plurality of substratesand high frequency electricity being applied to said electrodes, wherein

the processing apparatus is constituted such that processing gas issupplied into a space between the pair of electrodes.

A plasma processing apparatus according to still another aspect of thepresent invention, comprises:

a processing chamber in which a plurality of substrates are stacked andaccommodated,

a pair of electrodes extending in the stacking direction of theplurality of substrates, said electrodes being disposed at one side ofthe plurality of substrates, and high frequency electricity beingapplied to the electrodes, and

an electrical discharging chamber which is separated from the processingchamber and which includes a space between the pair of electrodes,wherein

a gas blowout opening for supplying the processing gas into theprocessing chamber is provided in the electrical discharging chamber.

In the above-mentioned batch-type remote plasma processing apparatusesaccording to each aspect of the present invention, when high frequencyelectricity is applied between the pair of electrodes, plasma isgenerated between the pair of electrodes. When the processing gas issupplied into this plasma atmosphere, active particles are formed, andif the active particles are supplied to the plurality of substrateswhich were transferred into a process tube, the plurality of substratesare collectively subjected to plasma processing.

Since the plurality of substrates to be processed are collectivelybatch-processed, it is possible to largely enhance the throughput ascompared with a case in which the substrates to be processed areprocessed one by one (single substrate-processing). Further, the entiresurface of each substrate can be heated uniformly by heating theplurality of substrates accommodated in the processing chamber by ahot-wall type heater. Therefore, processing of substrate by plasma canbe carried out uniformly.

Next, preferred embodiments according to the present invention will beexplained in detail.

First Embodiment

In this embodiment, as shown in FIGS. 1 to 3, a batch-type remote plasmaprocessing apparatus of the invention is formed as a batch-type verticalhot wall type remote plasma CVD apparatus (CVD apparatus, hereinafter).That is, a CVD apparatus 10 is made of material having high heatresistance such as quartz glass or the like. The CVD apparatus 10 isprovided with a cylindrical process tube 11. One end of the process tube11 is opened and the other end thereof is closed. The process tube 11 isvertically fixedly supported such that a center line of the tube 11 isvertically directed. A cylindrical hollow portion of the process tube 11forms a processing chamber 12 in which a plurality of wafers 1 areaccommodated. A lower end opening of the process tube 11 is formed intoa furnace opening 13 through which the wafer 1 as a subject to beprocessed is loaded and unloaded. An inner diameter of the process tube11 is set greater than a maximum outer diameter of the wafer 1 to behandled.

Heaters 14 for uniformly heating the entire processing chamber 12 areconcentrically provided around the process tube 11 such as to surroundthe process tube 11. The heaters 14 are supported by a machine frame(not shown) of the CVD apparatus 10 such that the heaters 14 are mountedvertically.

A manifold 15 abuts against a lower end surface of the process tube 11.The manifold 15 is made of metal. The manifold 15 is formed into acylindrical shape which provided at its upper and lower ends withflanges. The flanges project outward in a diametrical direction of themanifold 15. The manifold 15 is detachably mounted to the process tube11 for maintenance operation and cleaning operation for the process tube11. The manifold 15 is supported by a machine frame (not shown) of theCVD apparatus 10 and the process tube 11 is mounted vertically.

One end of an exhaust pipe 16 is connected to a portion of a sidewall ofthe manifold 15. The other end of the exhaust pipe 16 is connected to anexhaust apparatus (not shown) so that the processing chamber 12 can beevacuated. A seal cap 17 which closes a lower end opening of themanifold 15 abuts against the lower end opening of the manifold 15 fromvertically lower side through a seal ring 18. The seal cap 17 is formedinto a disc-like shape having substantially the same outer diameter asthat of the manifold 15. The seal cap 17 is moved up and down in thevertical direction by an elevator (not shown) which is verticallyprovided outside the process tube 11. A rotation shaft 19 passes througha center line of the seal cap 17. The rotation shaft 19 is moved up anddown together with the seal cap 17, and is rotated by a rotating drivingapparatus (not shown). A boat 2 which holds the wafers 1 as subjects tobe processed is vertically supported on an upper end of the rotationshaft 19 such as to stand thereon.

The boat 2 comprises a pair of upper and lower end plates 3 and 4, and aplurality of (three, in this embodiment) holding members 5 verticallydisposed between the end plates 3 and 4. Each the holding member 5 isprovided with a large number of holding grooves 6 which are disposed inthe longitudinal direction at equal distances from one another. Outerperipheral edge sides of the wafers 1 are respectively inserted into thelarge number of holding grooves 6 of the holding member 5. With thisdesign, the wafers 1 are arranged and held horizontally with respect tothe boat 2 such that centers of the wafers 1 are aligned to each other.A thermal insulation cap 7 is formed on a lower surface of the lower endplate 4 of the boat 2. A lower end surface of the thermal insulation cap7 is supported by the rotation shaft 19.

A gas supply pipe 21 for supplying processing gas vertically stands on aposition in the vicinity of an inner peripheral surface of the processtube 11 different from a position of the exhaust pipe 16 (at a positionon the opposite side from the exhaust pipe 16 through 180° in theillustrated example). The gas supply pipe 21 is made of dielectricmaterial, and is formed into a thin and long circular pipe. A lower endof the gas supply pipe 21 is bent into an elbow shape at right angles toform a gas introducing portion 22. The gas introducing portion 22 passesthrough a sidewall of the manifold 15 outward in the diametricaldirection, and projects outside. A plurality of blowout openings 23 areopened in the gas supply pipe 21 and arranged in the vertical direction.The number of blowout openings 23 corresponds to the number of wafers 1to be processed. In this embodiment, the number of blowout openings 23coincides with the number of wafers 1 to be processed, and a height ofeach blowout opening 23 is set such that each blowout opening 23 isopposed to a space between vertically adjacent wafers 1 held by theboat.

A pair of support cylinders 24 and 24 project outward in the diametricaldirection on opposite sides of the gas introducing portion 22 of the gassupply pipe 21 in the manifold 15 in the circumferential direction.Holder portions 26 and 26 of a pair of protect pipes 25 and 25 aresupported such that the holder portions 26 and 26 pass through thesupport cylinders 24 and 24 in the diametrical direction. Each theprotect pipe 25 is made of dielectric material, and is formed into athin and long circular pipe shape whose upper end is closed. Upper andlower ends of the protect pipes 25 are vertically aligned to the gassupply pipe 21. A lower end of each the protect pipe 25 is bent into anelbow shape at right angles to form a the holder portion 26. The holderportion 26 passes through the support cylinder 24 of the manifold 15outward in the diametrical direction and projects outside. A hollowportion of each the protect pipe 25 is brought into communication withoutside (atmospheric pressure) of the processing chamber 12.

A pair of thin and long rod-like electrodes 27 and 27 made of conductivematerial are concentrically disposed in the hollow portions of theprotect pipes 25 and 25. A portion-to-be-held 28 which is a lower end ofeach the electrode 27 is held by the holder portion 26 through ainsulative cylinder 29 and a shield cylinder 30 which prevent electricdischarge. A high frequency power source 31 is electrically connectedbetween both the electrodes 27 and 27 through a matching device 32. Thehigh frequency power source 31 applies high frequency electricity.

Next, a method for eliminating carbon existing in the vicinity of asurface of a Ta₂O₅ film for a capacitance portion of a capacitor of theDRAM using the CVD apparatus 10 having the above structure will beexplained. That is, in this embodiment, it is assumed that the wafer 1to be supplied to the CVD apparatus 10 is coated with a Ta₂O₅ film (notshown) for forming the capacitance portion of the capacitor by aprevious MOCVD step, carbon (not shown) exists in the vicinity of asurface of the Ta₂O₅ film, and the carbon is to be eliminated by the CVDapparatus 10.

A plurality of wafers 1 as substrates to be processed of the CVDapparatus 10 are charged to the boat 2 by a wafer transfer apparatus(not shown). As shown in FIGS. 2 and 3, the boat 2 into which theplurality of wafers 1 are charged is moved upward by the elevatortogether with the seal cap 17 and the rotation shaft 19, and is loaded(boat-loaded) into the processing chamber 12 of the process tube 11.

If the boat 2 holding the group of wafers 1 is loaded into theprocessing chamber 12, the processing chamber 12 is evacuated into apredetermined pressure or lower by an exhaust apparatus connected to theexhaust pipe 16, and a temperature of the processing chamber 12 isincreased to a predetermined temperature by increasing electricitysupplied to the heaters 14. Since the heater 14 is of the hot wall typestructure, a temperature of the processing chamber 12 is uniformlymaintained entirely and as a result, a temperature distribution of thegroup of wafers 1 held by the boat 2 also becomes uniform over theentire length, and a temperature distribution over the entire surface ofeach the wafer 1 also becomes uniform.

After a temperature of the processing chamber 12 reaches a preset valueand is stabilized, oxygen (O₂) gas is introduced as processing gas 41,and if a pressure thereof reaches a preset value, the boat 2 is rotatedby the rotation shaft 19 and in this state, high frequency electricityis applied between the pair of electrodes 27 and 27 by the highfrequency power source 31 and the matching device 32. The oxygen gaswhich is the processing gas 41 is supplied to the gas supply pipe 21,and if the high frequency electricity is applied between both theelectrodes 27 and 27, plasma 40 is formed in the gas supply pipe 21 asshown in FIG. 2, and reaction of the processing gas 41 becomes active.

As shown with broken arrows in FIGS. 1 and 2, activated particles(oxygen radical) 42 of the processing gas 41 are emitted from theblowout openings 23 of the gas supply pipe 21 into the processingchamber 12.

The activated particles (active particles, hereinafter) 42 are emittedfrom the blowout openings 23, and flow between the opposed wafers 1 and1 and come into contact with the wafers 1. Therefore, the contactdistribution of the active particles 42 with respect to the entire groupof wafers 1 becomes uniform over the entire length of the boat 2, and acontact distribution of the entire surface of each the wafer 1 in itsdiametrical direction which corresponds to a flowing direction of theactive particles also becomes uniform. At that time, since the wafer 1is rotated by rotation of the boat 2, a contact distribution of theentire surface of the wafer of the active particles 42 which flowbetween the wafers 1 and 1 also becomes uniform in the circumferentialdirection.

The active particles (oxygen radical) 42 which came into contact withthe wafers 1 thermally reacts with carbon which exists in the vicinityof a surface of the Ta₂O₅ film to generate CO (carbon monoxide), therebyeliminating carbon from the Ta₂O₅ film. At that time, as describedabove, the temperature distribution of the wafers 1 is maintaineduniform over the entire length of the boat 2 and over the entire surfaceof the wafer, and the contact distribution of the active particles 42with the wafers 1 is uniform over the all positions of the boat 2 andthe entire surface of the wafer. Therefore, the eliminating effect ofcarbon on the wafers 1 by the thermal reaction of the active particles42 becomes uniform over the all positions of the boat 2 and the entiresurface of the wafer.

Processing conditions for eliminating carbon from the Ta₂O₅ film to forma capacitance portion of capacitor of the DRAM are as follows: a supplyflow rate of oxygen gas used as the processing gas is 8.45×10⁻¹ to 3.38Pa·m³/s, a pressure in the processing chamber is 10 to 100 Pa, and atemperature thereof is 500 to 700° C.

If a preset processing time is elapsed, after supply of processing gas41, rotation of rotation shaft 19, application of high frequencyelectricity, heating of heaters 14, and evacuation of the exhaust pipe16 are stopped, if the seal cap 17 is lowered, the furnace opening 13 isopened, and the group of wafers 1 is transferred out from the processingchamber 12 from the furnace opening 13 (the boat is unloaded).

The group of wafers 1 transferred outside of the processing chamber 12is discharged (unloaded) from the boat 2 by the wafer transferapparatus. Thereafter, the above operation is repeated, therebycollectively batch processing the plurality of wafers 1.

According to the above embodiment, the following effects can beobtained.

1) The plurality of wafers are collectively batch processed. Therefore,it is possible to largely enhance the throughput as compared with a casein which the substrates to be processed are processed one by one. Forexample, the number of substrates which are processed per one hour whenthe substrates are processed one by one is five if the processing timeis 10 minutes and the operation time of a transfer system is twominutes. Whereas, the number of substrates which are batch processed perone hour is 66.7 if the processing time is 30 minutes and the operationtime of a transfer system is 60 minutes.2) By heating the plurality of wafers which were held by the boat andtransferred into the processing chamber by means of the hot wall typeheaters, it is possible to uniformly distribute a temperature of thewafers over the entire length of the boat and over the entire surface ofeach wafer. Therefore, it is possible to uniform the processing state ofwafers by the active particles which are formed by activating theprocessing gas by plasma, i.e., the eliminating distribution of carbonon the Ta₂O₅ film.3) By disposing the pair of thin and long electrodes in the processingchamber such that the electrodes are opposed to each other, it ispossible to form plasma over the entire length of both the electrodes.Therefore, it is possible to more uniformly supply the active particleswhich are formed by activating the processing gas by plasma, over theentire length of the group of wafers held by the boat.4) By disposing the gas supplying pipe in the space between the pair ofthin and long electrodes to which the processing gas is supplied, it ispossible to activate the processing gas by plasma in the gas supplyingpipe. Therefore, it is possible to prevent the wafer from being damagedby plasma, and it is possible to prevent the yield of wafers from beingdeteriorated by the plasma damage.5) The blowout opening is formed in the gas supplying pipe such that theblowout opening is opposed to a space between the upper and lower wafersheld by the boat. With this structure, the active particles are allowedto flow between the wafers. Therefore, it is possible to uniform thecontact distribution of the active particles with respect to the groupof wafers over the entire length of the boat. As a result, it ispossible to further uniform the processing state by the activeparticles.6) By rotating the boat which holds the plurality of wafers, the contactdistribution of the active particles which flowed between the wafers canbe uniformed over the entire surface of the wafer in the circumferentialdirection. Therefore, it is possible to further uniform the processingstate by the active particles.7) By eliminating the carbon of the Ta₂O₅ film used for the capacitanceportion of the capacitor of the DRAM, it is possible to reduce the leakcurrent between the electrodes of the capacitor. Therefore, it ispossible to enhance the performance of the DRAM.

Second Embodiment

A CVD apparatus of the second embodiment of the present invention willbe explained with reference to FIGS. 4 and 5.

The second embodiment is different from the first embodiment in that apair of electrodes 27A and 27B are disposed inside and outside of theprocess tube 11, and a gas supply pipe 21A is located at a positionother than a space to which the electrodes 27A and 27B are opposed.

In this embodiment, the high frequency electricity is applied betweenthe inner electrode 27A and the outer electrode 27B by the highfrequency power source 31 and the matching device 32, and if processinggas 41 is supplied to the processing chamber 12 by the gas supply pipe21A, plasma 40 is formed between a sidewall of the process tube 11 andthe inner electrode 27A, and the processing gas 41 is brought into areaction active state. The active particles 42 are dispersed over theentire processing chamber 12 so that the active particles 42 come intocontact with each wafer 1. The active particles 42 which came intocontact with the wafer 1 eliminate carbon which exists on the Ta₂O₅ filmof the wafer 1 by thermal reaction.

Third Embodiment

A CVD apparatus of the third embodiment of the present invention will beexplained with reference to FIGS. 6 to 8.

In the third embodiment, a pair of protect pipes 25 and 25 providedvertically along an inner wall surface of the process tube 11 are bentat lower portions thereof and pass through a side surface of the processtube 11. A pair of electrodes 27 and 27 are inserted through both theprotect pipes 25 and 25 from a lower portion of the side surface of theprocess tube 11. A guttering-like partition 34 forming a plasma chamber33 is disposed around an inner peripheral of the process tube 11 such asto air-tightly surround both the protect pipes 25 and 25. A plurality ofblowout openings 35 are arranged in the partition 34 such as to beopposed to a space between the upper and lower wafers 1 and 1. A gassupply pipe 21 is provided at a position of a lower portion of a sidesurface of the process tube 11 where gas can be supplied to the plasmachamber 33.

After the processing gas 41 is supplied to the plasma chamber 33 and apressure of the gas is maintained at a predetermined value, if the highfrequency electricity is applied between both the electrodes 27 and 27by the high frequency power source 31 and the matching device 32, plasma40 is formed in the plasma chamber 33 and the processing gas 41 isactivated. Activated electrically neutral particles 42 are emitted fromthe blowout openings 35 which are opened at the partition 34 and aresupplied to the processing chamber 12, and the particles come intocontact with each wafer 1 held by the boat 2. The active particles 42which came into contact with wafer 1 processes a surface of the wafer 1.

Fourth Embodiment

A CVD apparatus of the fourth embodiment of the present invention willbe explained with reference to FIG. 9.

This embodiment is different from the third embodiment in that the pairof electrodes 27 and 27 and their protect pipes 25 are located closer tothe partition 34 provided with blowout openings 35 than the process tube11.

If the protect pipes 25 are located closer to the partition 34 than theprocess tube 11 in this manner, it is possible to limit the gas flowbetween the protect pipe 25 and the partition 34. As a result, most ofprocessing gas pass between the two protect pipes 25, i.e., pass througha space having great plasma density.

Fifth Embodiment

A CVD apparatus of the fifth embodiment of the present invention will beexplained with reference to FIGS. 10 to 12.

A CVD apparatus of this embodiment includes a pair of thin and long flatplate-like electrodes 27C and 27C which are shorter than the processtube 11. Both the electrodes 27C and 27C are inserted, from outside ofthe process tube 11, into a pair of electrode insertion openings 36 and36 which extend in the vertical direction in a state in which theelectrodes 27C and 27C are in parallel to a portion of the sidewall ofthe process tube 11 and upper and lower ends of the electrodes 27C and27C are aligned to each other. A protect pipes 25C and 25C project froman inner peripheral surface of the process tube 11 such as to be opposedto the pair of electrode insertion openings 36 and 36, respectively.Inserting ends of the electrodes 27C and 27C are inserted into the pairof protect pipes 25C and 25C and surrounded. A distance between theelectrode insertion opening and protect pipe 25C is set slightly greaterthan a thickness of the electrode 27C so that the electrode 27C isexposed to atmospheric pressure. Connecting portions 28C and 28Crespectively project from lower ends of the electrodes 27C and 27C. Thehigh frequency power source 31 for applying high frequency electricityis electrically connected to the connecting portions 28C and 28C throughthe matching device 32. A flat plate-like partition 34C which forms aplasma chamber 33C in cooperation with both the protect pipes 25C and25C is provided between both the protect pipes 25C and 25C. A pluralityof blowout openings 35C are arranged in the partition 34C such as to beopposed to the upper and lower wafers 1 and 1. Processing gas 41 issupplied from the gas supply pipe 21 into the plasma chamber 33C.

After the processing gas 41 is supplied to the plasma chamber 33C by thegas supply pipe 21 and a pressure of the gas is maintained at apredetermined value, if the high frequency electricity is appliedbetween both the electrodes 27C and 27C by the high frequency powersource 31 and the matching device 32, plasma 40 is formed in the plasmachamber 33C and the processing gas 41 is activated. The activatedparticles 42 are emitted from the blowout openings 35C which are openedat the partition 34C and are supplied to the processing chamber 12, andthe particles come into contact with each wafer 1 held by the boat 2.The active particles 42 which came into contact with wafer 1 processes asurface of the wafer 1.

Sixth Embodiment

A CVD apparatus of the sixth embodiment of the present invention will beexplained with reference to FIGS. 13 to 15.

A CVD apparatus of this embodiment includes a discharge tube 38 forminga plasma chamber 37. The discharge tube 38 is made of dielectricmaterial, and is formed into a substantially triangular prism shapewhich is shorter than the process tube 11. The discharge tube 38 extendsin the vertical direction along a portion of an outer periphery of asidewall of the process tube 11. A plurality of blowout openings 39 arearranged in the sidewall of the process tube 11 surrounded by thedischarge tube 38 such as to be opposed to the space between the upperand lower wafers 1 and 1. The processing gas 41 is supplied from the gassupply pipe 21 to the plasma chamber 37 of the discharge tube 38. A pairof thin and long flat plate-like electrodes 27D and 27D which areshorter than the discharge tube 38 are provided on opposite sides of thedischarge tube 38 in its circumferential direction in a state in whichthe electrodes 27D and 27D are exposed to the atmospheric pressure. Thehigh frequency power source 31 which applies high frequency electricityis electrically connected to connecting portions 28D and 28Drespectively formed on the electrodes 27D and 27D through the matchingdevice 32.

After the processing gas 41 is supplied to the plasma chamber 37 by thegas supply pipe 21 and a pressure of the gas is maintained at apredetermined value, if the high frequency electricity is appliedbetween both the electrodes 27D and 27D by the high frequency powersource 31 and the matching device 32, plasma 40 is formed in the plasmachamber 37 and the processing gas 41 is activated. The activatedparticles 42 are emitted from the blowout openings 35C which are incommunication with the discharge tube 38 and are supplied to theprocessing chamber 12, and the particles come into contact with eachwafer 1 held by the boat 2. The active particles 42 which came intocontact with wafer 1 processes a surface of the wafer 1.

The above-described batch-type remote plasma processing apparatusesaccording to the preferred embodiments of the present invention arepreferably used for a substrate processing method for processing asubstrate, a film forming method and a semiconductor devicemanufacturing method.

The present invention is not limited to the above embodiments and can bevariously modified of course.

For example, the number of blowout openings of the gas supplying pipe isnot necessarily the same as the number of wafers to be processed, andmay be increased or decreased in correspondence with the number ofwafers to be processed. For example, the blowout opening is notnecessarily opposed to the space of the upper and lower adjacent wafers,and two or three blowout openings may be disposed between the adjacentwafers.

Although carbon existing on the Ta₂O₅ film of the capacitance portion ofthe capacitor was eliminated in the above embodiment, the batch-typeremote plasma processing apparatus of the present invention can also beapplied to a case in which a foreign matter existing on another film(molecule, atom or the like on other films) is to be eliminated, a casein which a CVD film is formed on a wafer, a case in which thermalprocessing is carried out, and the like.

For example, in a processing for nitriding an oxide film for a gateelectrode of a DRAM, a surface of the oxide film could be nitrided bysupplying nitrogen (N₂) gas, ammonia (NH₃) gas or nitrogen monoxide(N₂O) to a gas supplying pipe, and by heating a processing chamber to atemperature in a range from a room temperature to 750° C. A surface of asilicon wafer before silicon germanium (SiGe) film was formed wasprocessed by plasma using active particles of hydrogen (H₂) gas, anatural oxide film could be eliminated, and a desired SiGe film could beformed. When a nitrogen film was formed at a low temperature, if ALD(atomic layer deposition atomic layer film forming) in which DCS(dichlorosilane) and NH₃ (ammonia) were alternately supplied to form Si(silicon) and N (nitrogen) were formed one each, a high quality nitrogenfilm could be obtained by activating NH₃ with plasma and supplying thesame when NH₃ was supplied.

Although a wafer was processed in the above embodiment, a subject to beprocessed may be a photomask, a printed wiring substrate, a liquidcrystal panel, a compact disk, a magnetic disk or the like.

The entire disclosures of Japanese Patent Application No. 2001-3703filed on Jan. 11, 2001, Japanese Patent Application No. 2002-3615 filedon Jan. 10, 2002 and Japanese Patent Application No. 2002-203397 filedon Jul. 12, 2002 including specifications, claims, drawings andabstracts are incorporated herein by reference in their entireties.

Although various exemplary embodiments have been shown and described,the invention is not limited to the embodiments shown. Therefore, thescope of the invention is intended to be limited solely by the scope ofthe claims that follow.

1-9. (canceled)
 10. A substrate processing apparatus comprising: areaction tube which forms a space for accommodating a plurality ofsubstrates and processing the substrates; a wall member provided with aplurality of holes in a direction of stacking the substrates, and whichforms an electrical discharge space with a portion of a wall of thereaction tube; an electrode which is provided in the electricaldischarge space and which forms an activating region of the processinggas; and a gas supply section which supplies processing gas to theelectrical discharge space, wherein the plurality of substrates on whichfilm including attachment is formed is accommodated in the reaction tubeand high frequency electricity is applied on the electrode in a statewhere the processing gas is supplied in the electrical discharge spaceso that the processing gas including activated particles comes intocontact with the substrate to remove the attachment in the film.
 11. Thesubstrate processing apparatus as recited in claim 10, wherein theelectrode is a pair of electrodes extending in a direction of stackingthe substrate.
 12. The substrate processing apparatus as recited inclaim 11, wherein the electrode is a rod-like electrode.
 13. Thesubstrate processing apparatus as recited in claim 10, wherein theattachment is carbon and the activated particles are oxygen radicals.14. The substrate processing apparatus as recited in claim 13, whereinthe film is tantalum oxide film.
 15. A substrate processing apparatuscomprising: a reaction tube which forms a space for accommodating aplurality of substrates and processing the substrates; a wall memberprovided with a plurality of holes in a direction of stacking thesubstrates, and which forms an electrical discharge space with a portionof a wall of the reaction tube; an electrode which is provided in theelectrical discharge space and which forms an activating region of theprocessing gas; and a gas supply section which supplies processing gasto the electrical discharge space, wherein the plurality of substratesis accommodated in the reaction tube and high frequency electricity isapplied on the electrode in a state where the processing gas is suppliedin the electrical discharge space so that the processing gas includingactivated particles comes into contact with the substrate to removenatural oxide film from the surface of the substrate.
 16. The substrateprocessing apparatus as recited in claim 15, wherein the processing gasis hydrogen gas.